深低温保存大月龄胎儿血管和瓣膜组织的形态学评价

MORPHOLOGIC STUDY ON CRYOPRESERVED HOMOGRAFTS OF VALVED GREAT ARTERIES FROM LATE-PREGNANCY FETUS

①目的 用形态学方法评价深低温保存大月龄胎儿血管和瓣膜组织的效果。②方法 同种材料取自大月龄脑死亡胎儿。在冷冻保护液浸泡后置于 4℃冰箱冷平衡 ,特制无菌冷冻袋包装。用液氮蒸气梯度降温方法完成降温 ,- 1 96℃长期保存。复温后光镜、电镜观察血管组织形态并与复温前比较。③结果 修剪后和解冻后的血管及瓣膜细菌培养结果均为阴性。光镜、电镜观察显示解冻后的主动脉基本结构完整 ,胶原纤维和弹力纤维形态结构正常 ,排列规则 ,局部可见黏液样变性以及部分内皮细胞脱落。④结论 本法同种材料的取材、冷冻保存效果可靠。初步建立了综合采集、长期冻存大月龄胎儿血管和瓣膜组织的方法和技术标准 。

Objective To evaluate morphologically the effect of cryopreservation of homografts of valved great arteries from late-pregnancy fetus. Methods The homografts, which were obtained from healthy brain-dead fetuses, were soaked in cryoprotectant, equilibrated at 4 ℃, and packed in special freezing bags. Liquid nitrogen vapor was used to reduce the temperature to -196 ℃ to preserve the homografts. After the thawing, the vascular wall was observed by light microscope and electron microscope and the findings were compared with the normal ones. Results The results of the bacteria culture on the homografts were negative after the clipping and thawing. The light microscopy and electron microscopy showed the integrity of the basic structures of the thawed aorta, the normal structure of the collagen and elastic fibers, with part of vascular endothelium lost. Conclusion The findings of microscope and electron microscope confirm the reliability of the methods. We have set up a comprehensively collective, long-term cryopreserable method to preserve valved great arteries from late-pregnancy fetus for clinical application.